H. Tojo A. Ejiri M. P. Gryaznevich Y. Takase Y. Adachi
A method to determine the poloidal mode number m in a spherical tokamak based on magnetic probe data was developed. Perturbed magnetic fields at Mirnov coils are calculated for distributed helical filamentary currents on rational surfaces assuming the maximum current amplitude, m and n toroidal mode number, and the toroidal location of the filament…
PublishedG Van Oos M Gryaznevich E Del Bosco A Malaguias G Mank M Berta J Brotankova R Dejarnac E Dufkova I Duran M Hron P Peleman J Sentkerestiova J Stocke B Taf V Weinzett J Zajac S Zoletnik V Budaev N Kirneva G Kirnev B Kuteev A Melnikov
Small tokamaks may significantly contribute to the better understanding of phenomena in a wide range of fields such as plasma confinement and energy transport; plasma stability in different magnetic configurations; plasma turbulence and its impact on local and global plasma parameters; processes at the plasma edge and plasma-wall interaction; scena…
PublishedY. Liang H. R. Koslowski P. R. Thomas E. Nardon B. Alper P. Andrew Y. Andrew G. Arnoux Y. Baranov M. Bécoulet M. Beurskens T. Biewer M. Bigi K. Crombe E. De La Luna P. De Vries W. Fundamenski S. Gerasimov C. Giroud M. P. Gryaznevich N.
Type-I edge-localized modes (ELMs) have been mitigated at the JET tokamak using a static external n 1 perturbation field generated by four error field correction coils located far from the plasma. During the application of the n 1 field the ELM frequency increased by a factor of 4 and the amplitude of the D signal decreased. The energy loss per ELM…
PublishedYueqiang Liu M. S. Chu A. M. Garofalo R. J. La Haye Y. Gribov M. Gryaznevich T. C. Hender D. F. Howell P. De Vries M. Okabayashi S. D. Pinches H. Reimerdes EFDA-JET Contributors
Active control of the resistive wall mode RWM for DIII-D [Luxon and Davis, Fusion Technol. 8 , 441 (1985)] plasmas is studied using the MARS-F code [Y. Q. Liu, and et al. , Phys. Plasmas 7 , 3681 (2000)]. Control optimization shows that the mode can be stabilized up to the ideal wall beta limit, using the internal control coils I-coils and poloidal…
PublishedH. Reimerdes T. C. Hender S. A. Sabbagh J. M. Bialek M. S. Chu A. M. Garofalo M. P. Gryaznevich D. F. Howell G. L. Jackson R. J. La Haye Y. Q. Liu J. E. Menard G. A. Navratil M. Okabayashi S. D. Pinches A. C. Sontag E. J. Strait W. Zhu M
Dedicated experiments in the DIII-D tokamak J. L. Luxon, Nucl. Fusion, 42 , 614 2002, the Joint European Torus JET P. H. Rebut, R. J. Bickerton, and B. E. Keen, Nucl. Fusion 25 , 1011 1985, and the National Spherical Torus Experiment NSTX M. Ono, S. M. Kaye, Y.-K. M. Peng et al. , Nucl. Fusion 40 , 557 2000 reveal the commonalities of resistive wal…
PublishedG. Van Oost E. Del Bosco M. P. Gryaznevich A. Malaquias G. Mank
Small tokamaks may significantly contribute to the better understanding of phenomena in a wide range of fields such as plasma confinement and energy transport; plasma stability in different magnetic configurations; plasma turbulence and its impact on local and global plasma parameters; processes at the plasma edge and plasma-wall interaction; scena…
PublishedM. P. Gryaznevich E. Del Bosco A. Malaquias G. Mank G. Van Oost The IAEA CRP “Joint Research Using Small Tokamaks” Members
A new concept of interactive co-ordinated research using small tokamaks in the mainstream fusion science areas, in testing of new diagnostics, materials and technologies as well as in education, training and broadening of the geography of fusion research in the scope of the IAEA Co-ordinated Research Project (CRP) is discussed in this paper. Beside…
PublishedR. G. L. Vann R. O. Dendy M. P. Gryaznevich
Frequency sweeping (chirping) of high frequency magnetohydrodynamic modes is widely observed in tokamak plasmas. In this paper observations of chirping in neutral-beam-heated plasmas in the Mega-Amp Spherical Tokamak (MAST) [A. Sykes, R. J. Akers, L. C. Appel and et al. , Nucl. Fusion 41 , 1423 (2001)] are considered, and it is shown that these may…
PublishedS. Shiraiwa S. Ide S. Itoh O. Mitarai O. Naito T. Ozeki Y. Sakamoto T. Suzuki Y. Takase S. Tanaka T. Taniguchi M. Aramasu T. Fujita T. Fukuda X. Gao M. Gryaznevich K. Hanada E. Jotaki Y. Kamada T. Maekawa Y. Miura K. Nakamura T. Nish
A new operational scenario of advanced tokamak formation was demonstrated in the JT-60U tokamak. This was accomplished by electron cyclotron and lower hybrid waves, neutral beam injection, and the loop voltage supplied by the vertical field and shaping coils. The Ohmic heating (OH) solenoid was not used but a small inboard coil (part of the shaping…
PublishedR. J. Buttery O. Sauter R. Akers M. Gryaznevich R. Martin C. D. Warrick H. R. Wilson The Mast Team
Results from MAST provide a first test of neoclassical tearing mode physics in the spherical tokamak (ST). The mode accounts for the main performance limit in conventional tokamaks. Its behavior in the ST is remarkably well described by existing theoretical models, although it is more readily seeded by sawtooth events in these scenarios. Modeling c…
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